Pencil sharpening machine with a removable chip container



July 28, 1 959 N E. SATTMANN ETAL 2,896,578

PENCIL SHARPENING MACHINE WITH A REMOVABLE CHIP CONTAINER Filed June 11, 1956 /VVfA/TORS] Erfiar 5a flmanu z? wally will: elm) Scfifr 3, Q

United States Patent Q PENCIL SHARPENIN G MACHINE WITH A REMOVABLE CHIP CONTAINER Erhard Sattmann, Stein, near Nurnberg, and Willy (Wilhelm) Schafer, Numberg, Germany Application June 11, 1956, Serial No. 590,726

Claims priority,application Germany June 14, 1955 1 Claim. (Cl. 120-96) The present invention relates to a new and improved pencil sharpening machine with a removable chip container.

Prior to this invention, pencil sharpening machines have usually been provided with a chip container which was to be inserted or removed either at the side where the pencil was to be inserted or at the side transverse thereto. Either of these arrangements had the disadvantage that, particularly if the machine was not screwed down tightly to a stationary support, the chip container would easily slide out of the machine while the same was being operated or adjusted, or carried from one place of work to another, so that the chips would then fall out of the container and soil the place of work or the floor.

A further disadvantage of the prior pencil sharpening machines consisted in the fact that the lack of a spare cutter, when required to replace the worn-out cutter in the machine, usually rendered the machine useless entirely or at least until it was repaired at the factory or at a special service shop.

It is an object of the present invention to provide a pencil sharpening machine which overcomes the abovementioned disadvantage.

A further object of the invention is to provide a pencil sharpening machine with a removable chip container which is automatically prevented from sliding out of the machine due to the vibrations caused by the sharpening operation or while the machine is being carried from one place of work to another.

A feature of the invention for carrying out this object consists in the provision of a machine housing, one solid end wall of which is mounted directly on the machine base and preferably integrally therewith and carries the pencil clamping device, while the chip container is held within the housing so as to be removable therefrom in the direction toward the crank handle which is used for rotating the cutter. The shaft carrying the cutter is mounted in the end wall opposite to the solid wall previously mentioned so as to be easily rotatable therein so that, when the machine is not being operated, the weight of the crank and its handle will maintain the crank in a substantially vertical position, in which the crank will partly overlap the outer wall of the chip container and thus automatically lock the container and prevent it from falling out of the housing if the machine is carried from one place to another and not held in a level position. A similar condition prevails during the operation of the machine when the crank can only be turned when the container is at least substantially closed. For removing the chip container when it is necessary to empty the same, it will thus only be necessary to turn and hold the crank so as to point upwardly.

A further object of the present invention is to provide a pencil sharpening machine with a solid housing which is designed so as to permit the chip container to be easily removed therefrom and to allow the container to be easily inspected without requiring its removal from the machine to determine when it is time to empty it so "ice that the chips will not collect therein until the cutter will be clogged and thus fail to operate properly.

This object of the invention is attained by making the chip container or at least the opposite side walls thereof of transparent material, and providing the side walls of the machine housing with suitable cutouts through which the container may be easily grasped for its removal from the housing, and through which the inside of the containermay be easily inspected through the transparent Walls thereof to check the amount of its contents. Furthermore, according to the invention, each of these cutouts in the side walls of the housing is preferably made in the shape of a lying parabola which widens toward the end wall carrying the shaft and the upper end of which extends at least to a level which is even with the upper edge of the chip container. This shape of the cutouts, aside from permitting an easy access to and inspection of the chip container, has the further advantages that it will leave the side walls with the connecting end wall thereon of sufiicient strength to give the housing adequate stability, and that it will leave in one side wall underneath the inner end of the parabola-shaped cutout sufficient space to allow for the provision of a threaded opening for a horizontal compartment in the solid wall portion connecting the solid end wall with the base. This compartment is provided according to the invention to store a spare cutter for the machine. In order to permit an easy nemoval of this spare cutter from the compartment, a coil spring is preferably mounted at the bottom thereof which is held compressed by the cutter which, in turn, is maintained in the compartment by a screw plug which closes the mentioned opening in one side wall of the housing. Thus, when this screw plug is removed, the spane cutter will pop out under the pressure of the coil spring regardless of the position in which the machine might be held or be mounted. The coil spring is preferably secured within the compartment so as to prevent it from falling out and possibly getting lost.

Another very important advantage of this compartment is the fact that by being provided substantially at the apex between the main weight-supporting end wall and the base of the machine housing, and parallel to such end Wall and base, it forms a reinforcement underneath the tip of the parabola-shaped cutouts in the side walls which considerably stabilizes and rigidifies the end wall and prevents the same from pivotal vibrations when the machine is being operated which might otherwise occur due to the weakening of the side walls through the large cutouts therein. l

Still another feature of the invention resides in its simple form of construction which permits an easy and quick removal of the entire rotary unit of the machine, i.e. the shaft with the cutter and crank handle thereof, from the machine housing and a similar insertion or connection thereof to the housing. For this purpose, the bearing which supports the shaft is preferably made in the form of a flange which is provided with a bayonet lock, by means of which such bearing flange together with the shaft and the cutter and crank handle thereon may be quickly removed from one end wall of the hou ing for an inspection or cleaning of the cutter, whereafter the rotary unit may be quickly reattached and firmly locked to the end wall by a mere turn of the bearing flange.

These and further objects, features, and advantages of the present invention will be apparent from the following detailed description thereof, as well as from the accompanying drawings, in which Fig. 1 shows a side view of the new pencil sharpening machine;

Fig. 2 shows an end view of the machine, as seen from the right of Fig. 1;

Fig. 3 shows a cross section taken along line 3-3 of Fig. 1; while Fig. 4 shows a cross section taken along line 4--4 of Fig. 2.

Referring to the drawings, the housing of the new pencil sharpening machine consists of a machine base 2 with a solid vertical end wall 3 and curved side walls and 5' thereon. The upper part of end wall 3 carries a pencil clamp 4 of customarydesign; while each of side walls 5 and 5' has a cutout 6 of a contour in the shape of a lying parabola which widens toward the upper edge of base 2 and the rear end wall 3, respectively, which carries the crank 7.

The chip container or chip box 8 may, according to the invention, be inserted into and removed from the machine at the side facing toward crank 7. Such removal may, however, be carried out only if crank 7 is turned upwardly, as shown in Fig. 2. Since crank 7 when not in operation hangs vertically downward, it automatically prevents the chip box 8 from falling out of the machine if the latter is carried from one place of work to another. Chip box 8 is preferably made of a transparent material so that the cutouts 6 which extend at least to the upper edge 9 of chip box 8 allow at any time an inspection of its contents so that it may be emptied before the amount of chips collected exceeds its normal capacity and might clog up the cutter and prevent it from operating properly. The parabola shape of cutouts 6 has the further advantages that the side walls 5 and 5 will not be unduly weakened by these large inspection openings, and that underneath the re duced inner end of the parabola a space will be left in the side walls near the point of connection between end wall 3 and base 2. This space may be substantially filled out by substantially cylindrical compartment 10 which extends parallel to the end wall 3 and the base 2 and the wall of which serves as a reinforcement of the connection between end wall 3 and base 2 so as to rigidify' such end wall and compensate for the weakening in the structure through the provision of the large cutouts 6. This compartment 10 contains a coil; spring 12 which is preferably secured at one end to the bottom of the compartment. For this purpose, the lastcoil 15 of spring 12, before being inserted, may, for example, have a slightly larger diameter than the compartment 10 so that, after thespring is inserted, the resiliency of coil- 15 pressing against the bottom end of the side wall of the compartment will securely hold spring 12 Within the compartment. A spare cutter 11 may be inserted intov compartment 10 so as to compress spring 12, and it will thus be held therein when a screw plug 13- isscrewed into the mouth of the compartment. Ifthe. normal cutter which is installed in the machine at the factory should have become excessively dull, it is now no longer necessary to return the machine to the factory or to send it to a service shop to have the worn cutter reground or exchanged for a new cutter, but the machine may be easily and quickly reconditioned for further use within the oflice by any person of average mechanical dexterity. In order to remove the spare cutter 11 from the compartment 10, it is merely necessary to remove the screw plug 13, whereupon the cutter 11 will pop out under the propulsion of spring 12.

Although our invention has been illustrated and described with reference to the preferred embodiments thereof, we wish to have it understood that it is in no way limited to the details of such embodiments but is capable of numerous modifications within the scope of the appended claim.

Having thus fully disclosed our invention, what we claim is:

A portable pencil sharpener comprising a housing having a base, side and end walls, the upper portion of one of said end walls being provided with an aperture adaptedto receive the tip of a pencil to be sharpened, clamping means for said pencil carried by said end wall adjacent said aperture, a rotatable shaft supported by said housing adjacent said aperture, a cutter member carried by said shaft, a removable transparent chip container located within said housing and disposed beneath said cutter, the side walls of said housing being provided with parabolic-shaped cutouts facilitating removal of said chip container and being so disposed that the strength of said housing is not impaired, the apex of said parabolic-shaped cutouts extending in the direction of said end wall carrying said clamping means and in close proximity to said end wall, said housing being provided with a cylindrical compartment adjacent said apex of said cutouts and said base and adapted to receive a spare cutter member, a crank member carried by said shaft exteriorly of said housing and of suflicient weight that it will normally extend downwardly due to gravity towards said base in overlying relationship and directly in front of said chip container, thereby preventmg removal of said container and its contents during transporting of said pencil sharpener.

References Cited in the file of this patent UNITED STATES PATENTS 35,340 Walker May 20, 1862 350,330 Vedder Oct. 5, 1886 1,305,855 Wilson et al. June 3, 1910 1,390,517 Ensign Sept. 13, 1921 1,597,652 Kodan Aug. 24, 1926 2,544,319 Horowitz Mar. 6, 1951 FOREIGN PATENTS 193,169 Great Britain Feb. 22, 1923 

